Roll-supporting construction for centrifugal grinding mills



Feb. 25, 1930. W.'A. GIBSON Er-AL. I 8,

ROLL SUPPORTING CONSTRUCTION FOR CENTRIFUGAL GRINDING MILLS Filed 001;. 24, 1924 2 Sheets-Sheet l i 7 9 8 H lo l8 n J D \7 2S 6 23 6 3 Q 22 gg L 3| r I /l v 5 4 v 5 |nvenfo-rs.

William AXE-Mason dui' n es G. BurKe WWWA'M AU'ys:

2 Sheets-Sfieet 2 W. A. GIBSQIW ET AL" Filed 001?. 24, 1924 m w 0 s m mm w e VGBWW w. m 7 S 0 3 M m o 6 A A 1 15%" e llltl 1 kill W IIIIHWI: I'M k 4 a .=w WW. 4 m n Z a n0 6 6 Mfifiw? M A.

Feb. 25, 1930.

ROLL SUPPORTING cousmucnon FOR CENTRIFUGAL GRINDING ums "Patented r azs, 1930 7 wire!) STATES 'WILLIAM A. GIBSON AND JAIVIES G. BURKE, OF ALLENTOWN, PENNSYLVANIA, AS-

PATENT OFFICE stern-one, BY'MESNE ASSIGNMENTS, r BRADLEY rurvnmzn'n COMPANY, A conc 'IPORATION OF MASSACHUSETTS ROLL-SUPPORTING CONSTRUCTION FOR C'ENTRIFUGAL GRINDING MILLS Application filed 0ctobcr24, 1924-. Serial No. 745,574.

This invention relates to improvements in centrifugal grinding mills of the type in a which the material is' 'pulverized between a series of oentrifugally actuated crushing rolls and a co-operating annular die, and thegen- Vera l object of the invention is to provide a grinding mill of this character which is more simple and substantial in construction, more eflicient and economical in operation, and in which the wearand breakage of parts are re- I duced and worn parts more replaceable. c

economically illustrated in the following patents granted to the Bradley Pulverizer Company assignee respectively of Patent No. '1,175,436 E; C. 'Grri'tiith March 14-, 1916, and No. 1,473,341

, Gibson and Needham'November 6, 1923.7

- Qated crushing rolls are rotatably mounted upon the lower ends of shafts which arere- In mills of this type the centrifugally actuspectively secured in rocker heads which are 'pivotally mounted upon a rotatable carrier,

The rolls are provided with upwardly extend ing sleeves which embrace the shafts and bronze bushings are interposed between the rolls and their sleeves and the shafts.- In such construction the rolls have to be ac- ..curately boredand the sleeves and bushings accurately made.

In the operation of ,the

"machine the rolls and thebushings are subject to high heat particularly when clinker a. and other hot materials are being ground ent invention is to provide a construction in which the rolls-are rigidly secured to the I lower ends of the roll shafts, the necessity" for bushings between the roll and roll shaft beingthereby eliminated, thus reducingthe cost of construction, assemblage and replacement of the rolls and avoiding the S1lb]8C Q5 "sults in'crystallization of the shafts This grinding'chamber; I c x A furth r ob'ect of the invention is to pro- Oneoftheprincipal objects of the presthe, bushings to i the higu heat the ,l

is "accomplished by providing the rocker head upper and lower bearings located respectively upon opposite sides of the pivotal support of the rocker head in the rotatable carrier and in extending the sleeve clownwardly so that the lower bearing is preferably located in proximity to the roll, but above the highly heated zone of the die and co-operating roll.

provide improved means for lubricating the bearings for the roll shaft. This is accomplished'bv providing a chamber in the sleeve of the rocker head which will receive a large quantity. of lubricant and also providing sealing means at the bottom of the sleeve which will prevent the escape of lubricant there- A' further. object of the invention is to from so that the lubricant may be introt duced under pressure at the upper end of the sleeve by a grease gun or other suitable lubricant-forcing means.

A further object of the invention is to provide novel' anti-friction bearing mechanism for the roll shaft including a thrust bearing for supporting the roll and its shaft.

Other objects and features of the invention will more fully appear from the following description and the accompanying drawings and will be pointed out in the claims;

In the drawings: a

1 Fig. l is an elevation, partially in section, of a grinding mill of the type described, showing the embodiment of the invention therein; and,

Fig. 2 is a detail longitudinal sectional view through the rocker and its sleeve and through the grinding roll showing the roll shaft in elevation. I

The mill illustrated in the accompanying drawings comprises a bed 1 having an upturned annular curb 2 forming a pan adapted to receive the material to be ground. The annular curb isprovided with an upper detachable section 3 which co-operates with the lower section 2 to embrace and clamp therebetween an annular die 4. The base is provided with'lateral extensions 5 to which are secured the lower ends of preferably A-shaped frames 6 havingat their upper ends saddles 7 in which. a girder 8, which, extends dia metrically across the mill, is supported. This girder desirably is in the form of a slightly arched beam having a central preferably enlarged portion 9 having an aperture therethrough in which the central roll actuating shaft 10 is mounted. The roll actuating shaft 10 desirably is of tubular or quill shape and rotatably mounted upon a solid shaft 11 vwhich is rigidly secured at its bottom in a boss 12 pro ecting upwardly from the central portion of the base or pan 1. v I

The-quill shaft 10 is connected at its upper end to and supported by a beveled gear '13 the hub of which is journalled'in the central aperture in the beam 8. The beveled gear 13 is engaged and driven by a beveled pinion 14:

upon a driving shaft 15 which may be actuated in any suitable manner.

This construction may be and preferably is similar tothat "disclosed in Patent No. 1, 473,341.

Thequill shaft 10 has secured to it arotatable carrier 16 enerall circular-1n form o b i f V P n and provided with an annular rlange 1r which surrounds a stationary hopper member 18 21 which carry plows 22 projecting into the lower portion of the pan and which serves, during the rotatlon of the carrier to force the material in the pan into the path ofthe crush- 7 ing rolls.

The carrier is provided with radially extending arms or yokes in'which the trunnion shaft 23 is journalled in the usual manner.

The rocker head is in the form of 'a long sleeve 24 having a laterally extending boss'25 provided with an aperture to receive the trunnion shaft 23 and the outer wall of theboss desirably is split to .provide sections 26 and I .27 which may be drawn by a bolt-'28 to clamp the sections of the boss firmly upon the trunnion shaft 23.

The sleeve 24 is provided near its upper "1 end, preferably above the axis'of the trunion shaftfwith an inwardly extending annular rib 29'present1ng a flat shoulder 8O to support the thrust bearing which carries the roll which theiroll 33 is fixedly secured'by a nut shaft. The preferred form of roll shaft il .iustrated comprises a lower cylindrical portion 31 having a tapered lower end. 32 upon 34 upon a screw threaded reduced endpon ti'on 35 of the roll shaft, the nut 34 being lo-' cated in a countersink 36 in the roll. The

peripheral portion of the nut 35 desirably is provided W'lth a plurality of recesses 37'to receive a pin 38 which is driven into a suit able socket in'the roll soitha tthe nutis vented from *becoming'unscrewed.

' The roll shaft desirably is mounted in upl per and lower anti-friction hearings in the sleeve of the rocker head which are located respectively above and below the horizontal plane of the axis of the trunnion shaft 23.

Desirably the lower end ofthe sleeve extends into rather close proximity to the roll so that the upper and lower bearings are, separated a considerable distance apart; to Stabilize the shaft, thereby preventing the vibration of the roll from causing crystallization of the shaft. The sleeve portion ofthe rocker head desirably is of considerably larger diameter than the roll'shaft to provide alubricant chamber and is provided at its lower end with an enlarged cylindrical chamber .89 in -Wl1l-Cl1 an anti-friction bearing is mounted. In the embodiment of the invention illustrated the anti-friction bearing isin the forrnof a roller bearing the outer IEICQAO-Of which fits in the;

chamber 39 and the inner'race 41 of which is secured upon a reduced portion of theroll shaft; One or more series of rollers42 are "interposed between the inner and outer races.

In order to'preven-t the esc-ape of lubricant from the sleeve sealingvme-ans' are provided at the lower end of the sleeve "Such sealing means illustrated herein comprisean annular collar ilwhich fits uponlthe reduced portion of the rollshaft and has preferably a plu' rality of downwardly'extending ribs 44:

which intermesh with the grooves between complementary ribs 4511 11 a sealing plate 16 which is bolted to thelower end of t-he y The inner race 41' andthe'sleeve 43iipoii sleeve 24;.

the roll shaft are held in position bya nut 47 upon the roll shaft the lower face of which engages the upper end of therace 41 which r at its lower end engages the collar 4.3 so that 'when the nut is set up the race {lland collar 43 are clamped tightly against the shoulder formed by thejunction of the reduced section of the shaft with the section 31 thereof.

tends upwardly from the nut His of slightly smaller diameter and the upper portion of the roll shaft is provided with a section 48 of still further'reduced diameter whichpresents at its lower end a shoulder 19 to co The portion of the roll shaft which. ex

operate with a member of thethrust bearing; f p

The thrust bearing comprises a cage having an annular wall 50 which fits Vwithin'a' cylin- V i drical recess in the upper portion of the rocker head sleeve and rests at itsjlowe'r end upon the shoulder 80 of the ribg2g9. wear plate 51, which vlikewise .restsqupon the shoulder 30, supports aseries'ofrollers .52 V

which engage a collar 5310mm upon the reduced portion d8 of, the shaft "and which rests upon the shoulder 49 of the shaft. An-

other series of rollers 5413.1 6 interposed between the'. collar 53 and a hardened plate :55

whi h aims h /t p ft ebeafins cage. 1A.

- 'collar 56 rests upon the plate'55 andiis inter-33 cap 62.

pOsedb'etweenthe thrust bearing and the the upper bearing is spaced apart from'the colla'r52 upontheshaft'by a sleeve59. A

nut60, upon the upper endof the shaft which engages the upper edge of the inner race,

acts to clamp the inner'race 58, thesleeve 59 and the "collar 53 firmly'against the shoulder 49 of the shaft.

tween the outer race'57 and the inner race 58.

A series of rollers 61 is interposed beof this construction it will be obvious that the roll is supported by the collar, 53 and rollers 52 of the thrust bearing upon the wear plate 51, which rests upon the shoulder of I the rib 29 of the sleeve and that upward thrust is resisted by the'thrustbearing as the shoulder 49 engages the collar-53 which in turn is engaged by the series of rollers 54 which actupon the wear .plate55' and which wear plate is held from upward movement by the spacing collar 56, the outer race 55 and the D-es irably means are provided for supplying lubricant under pressure to the chamber within the sleeve as the lower end of the sleeve is so sealed as to prevent escape of lubricant therefrom. As illustrated herein the means for; receiving lubricant under pressure compr ses an 011 nut 64 which is secured in a suitable aperture in the cap 62. Of course, other forms of forced lubrication may be employed.

t It will be obvious that the roll shaftand its g anti-friction bearings can be readily assemabove and-below the axis of the trunnion, detrimental action upon the bearings caused bled'upon and removedfrom the sleeve and si-further that the bearings are so spaced apart as to give great stability to the shaft. The lowerbearing is. placed in as close proximity to the roll as is desirable, but is not within ings wh'en located within the roll. I

By reason of the location of the bearings by the continuous vibration of the roll is wholly obviated or greatly lessened and oval wearing of the bearings prevented. In the present construction the roll when worn can be removed by merely withdrawing the pin 38, removing the nut-34 and driving the roll from the shaft and a new roll replaced. This permits a great saving in the cost of the'rolls 1 over previous constructions in which 1t 1s necessary to discard the bronze bushings as well asthe worn roll-.1 v i a The present construct on permits the use of roller bearings thus saving considerable power heretofore required to drive the rolls and the largelubricant chamber in the sleeve with its seal at its lower end permits the use of a superior type of lubrication over that which has been required in mills as-heretoforc constructed. F It will be obvious that the particular embodiment of the invention as disclosed herein is of an illustrative character and that various changes in form, construction and ar- -1:-angement of parts may be made within the scope of the claims. It will-be also obvious that the application of the invention is not confined to the particular form of mills disclosed herein, but may be embodied in any mill of the same general type within the scope of the claims. a

; Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is: 1. In a centrifugal grinding mill of th class described comprising a roll shaft, a roll rigidly secured to the lower end thereof and a rocker head presenting a sleeve of greater internal diameter than the diameter of the roll shaft. to receive the roll shaft, anti-friction bearings for said roll shaft within said sleeve adjacent to the ends thereof providing a lubricant chamber between said bearings and sealing means at the lower end of the sleeve for preventing the escape of lubricant comprising concentrically arranged members secured respectively to the sleeve and shaft having closely intermeshing complementary annular ribs and grooves.

.ZJIn a centrifugal grinding mill of the class described comprising a roll shaft having a roll rigidly secured to the lower end thereof, and having a reduced cylindrical'portion presenting at its lower end a shoulder, a lower bearing race and a sealing member upon the reduced portion of said shaft, means for clamping the same against said shoulder, a rocker head presenting a long pivotally supported sleeve of greater internal diameter than the diameter of said roll shaft to receive said roll shaft and enclosing the reduced portion thereof, complementary lower bearing races surrounding said reduced portion of said shaft, a series of rollers intermediate of said bearing races and complementary concentrically arranged sealing memberssecured respectively to said shaft and sleeve below said bearing races.

4 8. In a centrifugal grindingn ill of the class described comprising a roll shaft having a roll rigidly secured to thelower end thereof, and having at its upper end a reduced cylindrical portion presenting a shoulder, a rocker head presenting an elongated sleeve to receivesaid roll shaft and provided I with an internal rib'presentinga shoulder lo ;cated above the pivotal support of said rocker head, an anti-friction-thrust bearing I r was for said shaft carried by said shoulder comprising a collar upon the reduced portion of.

said shaft and seated upon its shoulder, a roller bearingfor said shaftilocated above said thrust bearing comprising an inner race on said reduced portion of the shaft and an outer race in said sleeve With rollers therebetween, a collar on said sleeve intermediate" of said outer race and said thrust bearing, a

' cap on said sleeveclamping the outer race and collar upon the shoulder of the sleeve, a sleeve on said shaft intermediate of the in ner race and the thrust bearing, a nut on said 1 sleeve.

rib presenting a shoulder located above the a 4. In a centrifugal grinding mill of the class described comprising a roll shaft having a roll detachab'ly secured to the lower end thereof and'having at its upper end a reduced cylindrical portion presenting ashoulder, a

ngaging the upper end of sa d inn r race and clamping the same, the sleeve therebelow and the collar against the shoulder upon said shaftand a cap on said sleeve engaging the upper end of the outerrace-way 'acting to clamp said race-wayand thethrust bearing race-Way With the collar therebetvveefn' against the shoulder of the rocker sleeve and an antifriction bearing for said shaft adjacent the lower end of said sleeve, 7

' In t ny h r iwe ha e signe o r names to this specification. 1

' IAM GIBSQN- AM G BURKE rocker head presenting an elongated sleeve of greater diameter than that of said shaft and provided near its upper end with an internal pivotal support of said rocker head, a thrust bearing for said shaft comprising a bearing cage mounted upon the shoulder of said sleeve and having upper and, lower Wear plates, a collar on said shaft abutting the shoulder thereupon, upper and loWer series of rollers flocatedrespectively intermediate of said collar and saidupper and lower Wear plates,

means for clamping the bearing cage against the shoulder of the rocker sleeve, means on said shaft for clamping said collar against the shoulder of said shaft and anti-friction bearings for said shaft at the upper and lower ends of said rocker sleeve. 5. In a centrifugal grinding mill of the class described comprising a roll shaft ha.ving a roll detachably secured to the loWer end thereof and having at its upper end a reduced cylindrical portion presenting a shoulder, a rocker head presenting an elongated sleeve of greater diameter than that'of'sa'id shaft and provided near its upper 'endvvith an internal rib presenting a shoulder located above the pivotal support of said rocker head, a

thrust bearin for saidshaft com arisin a bearing cage mounted upon the shoulder of 3 said sleeve and having upper and lowerwear 'jplates, a collar'on saidshaft abutting the V shoulder "thereupon, upper 'and'lower series of rollers located respectively intermediate of I said {collar and said upper and lower wear 'plates, an upperrollerbearing for said shaft having inner andou-te'rraceays, a sleeve on said shaft between-"said inner race-way and ran 

